/*
 * Copyright 2002-2017 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.scripting.support;

import org.springframework.lang.Nullable;
import org.springframework.scripting.ScriptSource;
import org.springframework.util.Assert;

/**
 * Static implementation of the
 * {@link org.springframework.scripting.ScriptSource} interface,
 * encapsulating a given String that contains the script source text.
 * Supports programmatic updates of the script String.
 *
 * @author Rob Harrop
 * @author Juergen Hoeller
 * @since 2.0
 */
public class StaticScriptSource implements ScriptSource {

    private String script = "";

    private boolean modified;

    @Nullable
    private String className;


    /**
     * Create a new StaticScriptSource for the given script.
     *
     * @param script the script String
     */
    public StaticScriptSource(String script) {
        setScript(script);
    }

    /**
     * Create a new StaticScriptSource for the given script.
     *
     * @param script    the script String
     * @param className the suggested class name for the script
     *                  (may be {@code null})
     */
    public StaticScriptSource(String script, @Nullable String className) {
        setScript(script);
        this.className = className;
    }

    /**
     * Set a fresh script String, overriding the previous script.
     *
     * @param script the script String
     */
    public synchronized void setScript(String script) {
        Assert.hasText(script, "Script must not be empty");
        this.modified = !script.equals(this.script);
        this.script = script;
    }


    @Override
    public synchronized String getScriptAsString() {
        this.modified = false;
        return this.script;
    }

    @Override
    public synchronized boolean isModified() {
        return this.modified;
    }

    @Override
    @Nullable
    public String suggestedClassName() {
        return this.className;
    }


    @Override
    public String toString() {
        return "static script" + (this.className != null ? " [" + this.className + "]" : "");
    }

}
